Cannot declare functions when there is "import" statement

This is my rplugin (actually I just copied from the prototype example)

function MyPlugin(plugin) {
  this.plugin = plugin;
  plugin.registerFunction('MyFunc', [this, MyPlugin.prototype.func]);
}

MyPlugin.prototype.func = function() {
  this.plugin.nvim.setLine('A line, for your troubles');
};

export default MyPlugin;

If I save it to ~/.config/nvim/rplugin/node/myplugin/index.js then run :UpdateRemotePlugins | !cat ~/.local/share/nvim/rplugin.vim, then the result show that the function MyFunc has been registered. But if I just add this line to the top of the file index.js

import { abort } from "process";

Running :UpdateRemotePlugins | !cat ~/.local/share/nvim/rplugin.vim again and it show that the function MyFunc is not registered

Start with the rplugin file at ~/.config/nvim/rplugin/node/myplugin/index.js and compare the output of :UpdateRemotePlugins | !cat ~/.local/share/nvim/rplugin.vim with and without the import statement. Done means MyFunc remains registered after the import is present.